public void PropEach() { Action <Dictionary <string, object>, int> callback = (Dictionary <string, object> obj, int i) => { Assert.AreEqual(obj, new Dictionary <string, object>() { { "a", 1 } }); Assert.AreEqual(i, 0); }; Turf.PropEach(pointFeature, callback); var pointCollect = Collection(pointFeature); Turf.PropEach(pointCollect, callback); }